Just months after Tampa International Airport heralded its first charter flights to Cuba in nearly 50 years, the future of not just the flights but all less-restrictive travel to the island nation is threatened.

A proposal in Congress to roll back the Obama administration's broad opening of travel to Cuba has been tethered to a huge, year-end spending bill. Though President Barack Obama opposes the revival of Cuba travel restrictions, legislators on both sides of the aisle say it will be difficult for him to block if it is included in the version of the spending bill that reaches his desk.

U.S. Rep. Mario Diaz-Balart, R-Miami, inserted the tightened restrictions in July, but they surfaced publicly this week as the spending bill moved through Congress.

Opponents blasted the measure as both ill-conceived and ill-placed, because it's included in a spending bill and not as a separate policy measure.

"We must not go back to the days when sons and daughters, brothers and sisters, and grandsons and granddaughters were unable to visit sick or dying relatives in Cuba," U.S. Rep Kathy Castor, D-Tampa, wrote in a letter to conferees working on legislation.

More than 80,000 Cuban-Americans live in the Tampa Bay area, the third-largest U.S. population after South Florida and metro New York.

"I have no idea who they think they're helping. This would be a huge step backward for families and a huge step backward for the state of Florida," said Tessie Aral, president of ABC Charters in Miami, which began offering charter flights to Cuba out of Tampa in September.

"I have 27 employees right now on payroll. If this passes, I may have to go down to six," Aral said. "Guess what. (Service out of) Tampa is going to be the first one that is going to get closed down."

TIA now offers four flights a week to Cuba, three of them to Havana and one to Holguin on the eastern side of the island. It's one of just two U.S. airports that offers flights to more than one city in Cuba.

"We're certainly hoping this (legislation) doesn't go through. There would definitely be a financial impact," said TIA spokeswoman Janet Zink. "The flights have been really popular. There's been a lot of pent-up demand in the Tampa area."

By year-end, the airport projects nearly 8,000 passengers will have traveled to and from Cuba through the new service. Looking ahead, TIA projects that more than 43,000 passengers will take advantage of the Cuba flights in 2012, generating nearly $657,000 in airline and passenger spending and fees at the airport.

The Diaz-Balart measure would return the restrictions to levels set by President George W. Bush: only one trip every three years for "family reunifications," a cap on remittances of $1,200 per year and a tighter definition of "family."'

The Treasury bill that includes the Diaz-Balart amendment is one of the nine end-of-year U.S. government spending measures rolled into one now under consideration by the House and Senate. The two chambers are trying to agree on a compromise version before the holiday recess.

Within the Cuban-American community, the question of how far to go in restoring ties to the Cuban regime has long been both politically and emotionally charged. It's not a simple issue, not even among some using the new flights.

Cuban-American Arturo Rodriguez, who lives in Spring Hill, was among the first to fly out of Tampa to Havana when service began in September. For Rodriguez, 82, the flight marked his first trip back since Fidel Castro took power in 1959.

His long-awaited reunion with his brother and sister in Cuba was marred, though, by seeing how parts of his beloved homeland had become dirty and dilapidated.

"When I left Cuba in 1959 it was very nice," he said. "Now it's destroyed completely. … It's sad."